Bittousy

I have issues. The people that know and love me, love me in spite of them. I am having an issue and I don't know how to deal with it.
We threw a baby shower lunch thing for a co-worker of mine today. She's a nice enough lady, having her third child, a girl. She wasn't looking to get pregnant. Things happen though, and she's happy about it. I'm happy for her, mostly.
She's having a girl and I find myself feeling bitter and jealous, bittous.
Oscar was supposed to be a girl. Throughout my entire pregnancy, I swore that all I wanted was a healthy baby, that I didn't care if it was a boy or girl, just healthy. To a degree, that was true. But something in me came alive during the ultrasound when the perinatologist told me we were having a girl. I want a daughter. I have always wanted a daughter. I love my sons more than I love life itself, but I feel incomplete. When Oscar was born and they told me he was a boy, and not the daughter I had planned for, I wanted to cry. I don't know if I can explain this very well. It makes perfect sense in my head, but, like a lot of things in my head, may not translate well into intelligble language. I felt as if I'd gained and lost someone at the same time. From the moment the dr. told me it was a girl, she had a name. I said her name outloud and she became real. She became my daughter, a real, living, thriving human being. I spoke to her. I sang to her. I made plans for her. I knew her. I didn't know him. I felt as if I'd lost her, almost as if she'd died. And I felt like I had been handed a baby I didn't know. There was an instant disconnect-not from my son, but from the situation. I have bonded with my son, but I still have not been able to take apart the nursery we prepared for her so that we can make it boy-friendly.
I find myself feeling bittous toward complete strangers who happen to wander by me with their baby girls. I just had a baby. I should be happy. Everything went really well, and he is the picture of health. He is a great baby and relatively easy. I don't resent him, or blame him for having a penis. But I want her. I want them both.
This whole thing is stupid. I need to get over it and just accept that I don't have a daughter and that I may never have her. But I haven't been able to. My brain just won't let it go.
For the longest time I felt like the worst mother in the world because I was sad. I couldn't just be happy that I had a healthy baby boy. My joy and happiness in his arrival and existence was, and is, tempered by the sadness of not having her. I think that makes me crazy. I don't want my son to grow up thinking that I didn't want him or that he wasn't enough for me. I do want him. He is enough for me in that he is my son, and I love him for who he is and will love him for whatever he becomes.
But there is that empty place inside me waiting for her. I don't know what I'll do with it if she never comes.